How to compare hoodie and T-shirt fabric weight (GSM)

GSM means grams per square metre of fabric. A 400 GSM fabric would weigh 400 grams for one square metre. A finished hoodie includes multiple fabric pieces and may have ribbing, hardware or other materials, so its packaged weight is a separate measurement. ASTM describes fabric weight as mass per unit area. ASTM fabric weight test methods

Compare similar fabrics first

AS Colour lists a 400 GSM hoodie in its hoodie guide and a 220 GSM cotton tee in its tee guide. The figures describe different fabrics made for different garments. For a useful side-by-side comparison, start with two hoodies or two tees, then check whether their main fabrics have a similar construction and fibre blend. A seller can give a GSM figure while leaving the inside finish, blend or feel unclear. AS Colour hoodie specifications · AS Colour T-shirt specifications

Turn a vague claim into a buying question

• Ask whether the advertised GSM describes the main body fabric and applies to your chosen colour or variant.
• Ask for the fibre blend and a close photo of the inside surface if you want a particular finish, such as loopback or brushed fleece.
• If shipping weight matters, ask for the actual packed weight separately. For two listings with only the word “heavyweight”, record the fabric weight as unknown until you get a usable number.

Use GSM to narrow a shortlist when the other details line up. For example, if both options use a similar cotton jersey and you want the lighter fabric, compare their stated GSM before checking the listing’s measurements. For more listings to compare, browse the iTaoBuy Spreadsheet hoodie shortlist or the T-shirt shortlist.